(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
 (2) Issued:20170723/2235Z
 (3) Volcano:Sheveluch (CAVW #300270)
 (4) Current Aviation Color Code:ORANGE
 (5) Previous Aviation Color Code:orange
 (6) Source:KVERT
 (7) Notice Number:2017-170
 (8) Volcano Location:N 56 deg 38 min E 161 deg 18 min
 (9) Area:Kamchatka, Russia
(10) Summit Elevation:10768.24 ft (3283 m), the dome elevation ~8200 ft (2500 m)
(11) Volcanic Activity Summary:Strong gas-steam activity of the volcano possibly with small amount of ash continues, but ash explosions are not noting at now. Large explosive event occurred at 1740 UTC on 23 July, 2017. Explosions sent ash up to 11.5-12 km a.s.l., strong pyroclastic flows were observed. Ash cloud continues to drift to the north-east (azimuth 84 degrees) from the volcano, its front was lacated for about 698 km from the volcano at 2210 UTC on 23 July (according to Himawari-8).

Explosive-extrusive eruption of the volcano continues. Ash explosions up to 32,800-49,200 ft (10-15 km) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.
(12) Volcanic cloud height:NO ASH CLOUD PRODUSED
(13) Other volcanic cloud information:NO ASH CLOUD PRODUSED
(14) Remarks:
(15) Contacts:Dr. Olga A. Girina, Head of KVERT, IVS FEB RAS
girina@kscnet.ru +74152202044

Duty scientist: +79622825253
(16) Next Notice:A new VONA will be issued if conditions change significantly or the Aviation Color Code is changes. VONAs are posted at http://www.kscnet.ru/ivs/kvert/index_eng.php.

In Russia, KVERT, on behalf of the Institute of Volcanology and Seismology (IVS) FEB RAS, is responsible for providing information on volcanic activity to international air navigation services for the airspace users.

CITATION GUIDELINES

For formal scientific citation of this VONA/KVERT Information Release, please use the following:
VONA/KVERT Information Release, July 23, 2017. KVERT, Institute of Volcanology and Seismology FEB RAS. URL: http://www.kscnet.ru/ivs/kvert/van/?n=2017-170.
Aviation Colour Codes

GREEN

Volcano is in normal, non-eruptive state

   or, after a change from a higher level:

Volcanic activity considered to have ceased, and volcano reverted to its normal, non-eruptive state.

YELLOW

Volcano is experiencing signs of elevated unrest above known background levels.    

 or, after a change from higher level:

Volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.

ORANGE

Volcano is exhibiting heightened unrest with increased likelihood of eruption.

   or,

Volcanic eruption is underway with no or minor ash emission.
[specify ash-plume height if possible]

RED

Eruption is forecast to be imminent with significant emission of ash into the atmosphere likely.

  or,

Eruption is underway with significant emission of ash into the atmosphere.
[specify ash-plume height if possible]